Apparatus for the optical manipulation of a pair of landscape stereoscopic images

ABSTRACT

Apparatus ( 204 ) for optical manipulation of a pair of landscape stereoscopic images, such that the side-by-side orientation needed by a pair of human eyes is reoriented to an orientation which is required for recording with a single camera. The apparatus comprises three periscopes ( 108, 124, 130 ), two of which are horizontally oriented and one which is vertically oriented. The side-byside view is reoriented to an arrangement with one picture above the other. To achieve this one side view is reflected by one horizontal periscope ( 108 ) with first and second reflectors ( 120, 122 ) to an upper picture position. The other side view is reflected by the vertical periscope ( 124 ) with third and fourth reflectors ( 126, 128 ) to a lower position, where another horizontal periscope ( 130 ) with fifth and sixth reflectors ( 132, 134 ) reflects the other side view of a lower picture position. Thus, the optical axis exit the third periscope ( 130 ) below the optical axis exit of the first periscope ( 108 ). The pictures may be recorded without rotating. The apparatus may be used to view pictures which are recorded one above the other.

BACKGROUND OF THE INVENTION

This invention relates to apparatus for the optical manipulation of apair of landscape stereoscopic images.

In Christian WO 01/56301 there is disclosed apparatus for the opticalmanipulation of a pair of landscape stereoscopic images. The apparatusre-orientates a pair of landscape stereoscopic images between a firstorientation required for human viewing and a second orientation requiredfor recording with a single camera or for reproduction from a singlescreen.

The present invention aims to further the concept of imagere-orientation to produce apparatus suitable for operators who prefer touse a camera pointing at a photographic subject instead of sidewaysorientation.

BRIEF SUMMARY OF THE INVENTION

Accordingly, the present invention provides apparatus for the opticalmanipulation of a pair of landscape stereoscopic images, which apparatuscomprises a housing, and optical re-orientation means positioned in thehousing and for re-orientating the pair of landscape stereoscopic imagesbetween a first orientation selected from one of the orientations fromthe group consisting of top and bottom orientation and side-by-sideorientation required for human viewing and a second orientation beingthe other orientation of the group required for recording with a singleexternal camera positioned adjacent to the apparatus and viewed from asingle screen, the single screen being such that it has a first pair ofsides which are shorter than a second pair of sides, the secondorientation being such that there is no top to bottom inversion of oneof the landscape stereoscopic images with respect to the other of thelandscape stereoscopic images, the second orientation being such thatthe landscape stereoscopic images are rotated for display in each of twohalves of the single screen such that longest sides of the landscapestereoscopic images are parallel with the first pair of sides of thescreen thereby maintaining a good aspect ratio without the need forcompression or stretching of the pair of landscape stereoscopic images,and the optical re-orientation means being such that the pair oflandscape stereoscopic images leave the optical re-orientation means ina direction which is parallel to a direction in which the pair oflandscape stereoscopic images enter the optical re-orientation means,and the apparatus being characterised in that the optical re-orientationmeans comprises:

-   -   (i) a first periscope arrangement which is horizontally        disposed, and which comprises first and second reflective        surfaces;    -   (ii) a second periscope arrangement which is vertically        disposed, which comprises third and fourth reflective surfaces,        with the third reflective surface being the lower reflective        surface for reflecting out image light towards the single        camera; and    -   (iii) a third periscope arrangement which is horizontally        disposed, which comprises fifth and sixth reflective surfaces,        wherein the fifth reflective surface is facing and aligned with        the third reflective surface of the second periscope        arrangement, and which is such that the sixth reflective surface        is positioned underneath the second reflective surface so that        the optical axis of the exit of the third periscope arrangement        is directly underneath the optical axis of the exit of the first        periscope arrangement.

The reflective surfaces may be prism reflective surfaces or mirrorreflective surfaces.

The apparatus of the invention may be one in which the separation of twolenses, analogous to eye separation distance, is able to be varied belowa maximum.

The apparatus of the invention may be one in which the left edges andthe right edges of the stereoscopic pair of images are able to bealigned by rotation of the first reflective surface about a verticalaxis.

At least some of the reflective surfaces may be located in blocks.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Embodiments of the invention will now be described solely by way ofexample and with reference to the accompanying drawings in which:

FIG. 1 shows first apparatus according to WO 01/56301 for the opticalmanipulation of a pair of landscape stereoscopic images;

FIG. 2 shows second apparatus according to WO 01/56301 for the opticalmanipulation of a pair of landscape stereoscopic images;

FIG. 3 shows third apparatus according to WO 01/56301 for the opticalmanipulation of a pair of landscape stereoscopic images;

FIG. 4 shows how a television or monitor display according to WO01/56301 can be viewed through polarising spectacles or a lenticularoverlay;

FIG. 5 shows first apparatus of the invention for the opticalmanipulation of a pair of landscape stereoscopic images; and

FIGS. 6-9 show second apparatus of the invention for the opticalmanipulation of a pair of landscape stereoscopic images.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, there is shown apparatus 2 for the opticalmanipulation of a pair of landscape stereoscopic images. The apparatus 2comprises a housing 4 which is shown in exploded form for ease ofunderstanding. The apparatus 2 also comprises optical re-orientationmeans 6 which is positioned in the housing 4 and which is forre-orientating the pair of landscape stereoscopic images between a firstorientation required for human viewing and a second orientation requiredfor recording with a single camera or for reproduction from a singlescreen, the single screen being such that it has a first pair of sideswhich are shorter than a second pair of sides. The second re-orientationis also such that there is no top to bottom inversion of one of thelandscape stereoscopic images with respect to the other of the landscapestereoscopic images. The second orientation is further such that thelandscape stereoscopic images can be rotated for display in each of twohalves of the single screen such that the longest sides of the landscapestereoscopic images are parallel with the first pair of sides of thescreen, thereby maintaining a good aspect ratio without the need forcompression or stretching of the pair of landscape stereoscopic images.

The optical re-orientation means 6 is further such that the pair oflandscape stereoscopic images leave the optical re-orientation means 6in a direction which is parallel to a direction in which the pair oflandscape stereoscopic images enter the optical re-orientation means 6.

As shown in FIG. 1, the optical re-orientation means 6 comprises twomirrors 8, 10 which just reflect light, and a mirror 12 which bothreflects and transmits light. The mirror 12 is a half silvered mirrorwhich reflects substantially 50% of the light and which transmitssubstantially 50% of the light. The optical re-orientation means 6further includes polarising filters in the form of a polarising frame 14and polarising spectacles 16. The mirror 12 may have a metal or ametallic-type material other than silver for giving the 50% reflectionand the 50% transmission of the light.

Images are viewed via the polarising spectacles 16 from a television 18having a base 20, a top 22 and sides 24, 26. The television 18 is thusstanding in a normal upright position with its screen facing the housing4.

The mirror 12 is positioned between the mirror 8 and the mirror 10. Afirst polarising filter 28 is positioned in the polarising frame 14 suchthat it is between the television screen and the mirror 8. A second andcontrastingly polarised filter 30 is positioned in the polarising frame14 such that it is between the television screen and the mirror 12.

The mirror 8 is hinged about an edge 32, allowing the viewing apparatusto adapt for a smaller screen size. The mirror 12 makes an angle of 45°as shown.

In the apparatus 2, the light path of the original image has been foldedto avoid the need for rotating the display screen.

The upper mirror 10 may advantageously be hinged about its upper edge.Slight adjustment of its normal 45° angle then facilitates viewing froma variable vertical position.

Referring now to FIG. 2, there is shown second apparatus 52 for theoptical manipulation of a pair of landscape stereoscopic images. Theapparatus 52 comprises a housing 54 which is shown in exploded form forease of understanding. The housing 54 contains mirrors 56, 58, 60 and62. The mirrors 56, 60 are both mounted with their reflecting surfacesangled downwardly. The mirrors 58 and 62 are both mounted with theirfull reflecting surfaces angles upwardly. The mirror 56 may be rotatableabout its upper edge 64 to enable stereoscopic viewing of a smallerpicture display panel.

The mirror 62 may be rotated about a horizontal axis CD or,alternatively, its enclosure distance from a right eye arrangement 66may be changed to facilitate a human brain merging the images from theright eye arrangement 66 to a left eye arrangement 68 for eyeseparations which differ. The axis CD may coincide with upper or lowerhorizontal mirror edges, or be intermediate.

Although the apparatus 52 is shown in exploded form for clarity, inpractice, the apparatus 52, as with the apparatus 2, needs to excludelight from entering the eyes from anywhere but the appropriate part ofthe apparatus, in common with monoscopic use of a view finder. Theoptical re-orientation means needs to be enclosed, usually with theappropriate use of eye cups. Internal nor-reflective surfaces may bematt black. A vertical partition of the images may be essentially opaqueand it may extend to the height and width of the mirror 60.

As can be seen from the lower part of FIG. 2, the pair of landscapestereoscopic images are marked L, R and they are provided on a screen 70with a two-axes swivel mounting 72 by a camcorder (remainder not shown).The camera display screen is able to show such a pair of images by meansof an optical manipulation camera attachment to the lens described inUnited Kingdom Patent No. 2236198. As can also be seen from FIG. 2, theimages L, R are able to be seen one above the other, with the apparatus52 enabling each image L, R to be directed separately to the appropriateeye, at the right eye arrangement 66 and the left eye arrangement 68,this being in the manner of looking downwards into a pair of binoculars.

The apparatus 52 offers the choice of viewing with or without polarisingglasses 16. The glasses are no advantage in this case.

The apparatus 52 may be used with 180° rotation in principal, so thatthe eye-pieces become swapped over. The right eye image would bedirectly beneath the left eye-piece, instead of the left eye image onthe screen being below the right eye-piece as shown in FIG. 2.

Referring now to FIG. 3, there is shown apparatus 82 for the opticalmanipulation of a pair of landscape stereoscopies images. The apparatus82 is in the form of an endoscope.

The apparatus 82 comprises an optical channel positive lens element 84for the left eye view, and an optical channel positive lens element 86for the right eye view. There is also an optical channel negative lenselement 88 for the right eye view. A patient's body is shownschematically as body surface 90 and it will be seen that the right handend of the apparatus 82 is in the patient, whilst the left hand end ofthe apparatus 82 is outside the patient.

The apparatus 82 further comprises a prism reflective surface 92 for theright eye view. This prism reflective surface 92 gives a firstreflection which is upwards.

The apparatus 82 further comprises a prism reflective surface 94 for theright eye view. This prism reflective surface 94 gives a secondreflection which is directed towards the surgeon. A prism reflectivesurface 96 for the right eye view gives a third reflection which isdirected across and towards the left eye view optical axis, but aboveit. A prism reflective surface 100 for the right eye view provides afourth reflection which is directed parallel to the left eye viewchannel, but directly above it.

Also shown in FIG. 3 are a positive lens element 102 at the camera endof the right eye view channel, and a positive lens element 104 at thecamera end of the left eye view channel. A common focus 11 is shared bythe relay elements 86, 88. The magnification is given by the ratio ofthe focal lengths.

The right eye view 106 and the left eye view 108 are capturedsimultaneously by a single camera. The reference numeral 110 is shown asa discontinuous line in the left eye view purely for clarity. The lefteye channel is in principal a straight monoscopic endoscope.

The reference numeral 112 indicates a right eye view from the bottompatient end of the apparatus 82. The reference numeral 114 illustratesthe left eye view from the bottom patient end of the apparatus 82. Acommon target 116 is shown being viewed by both the left and right eyes.The optical axes are made to converge on the common target 116.

Optical relays in the form of pairs of lenses are represented at bothends of the right eye channel to illustrate the principal. In reality,the optical relays may consist of standard endoscope rod lenses whichrepeat along the length of the endoscope.

Because the apparatus 82 shown in FIG. 3 is in the form of an endoscope,illumination would normally be required to be directed down theendoscope, for example by optical fibre bundles (not shown). Therequired illumination may be fed in from the side of the apparatus 82. Acamera lead (not shown) may come in from the left of the apparatus 2.

FIG. 4 shows self-explanatory views of a television display throughpolarising spectacles or a lenticular overlay. The vertical strips atthe bottom represent reassembled picture elements where there-orientation of the images has been implemented in the manner of FIG.5 of WO 01/56301.

Referring now to FIG. 5, there is shown apparatus 202 of the presentinvention for the optical manipulation of a pair of landscapestereoscopic images. The apparatus 202 is shown in exploded wire frameform for clarity of illustration.

The apparatus 202 is in the form of a camera attachment. The apparatus202 comprises a housing 204 and optical re-orientation means 106. Theapparatus 202 is attached to a camera, which is not shown in FIG. 5 forclarity of illustration. The direction of attachment and the approximatepositioning of the apparatus 202 to the camera is shown by arrow 107.

The optical re-orientation means 106 comprises a first periscopearrangement 108 which is horizontally orientated, which has first andsecond reflective surfaces 120, 122 respectively.

The optical re-orientation means 106 further comprises a secondperiscope arrangement 124 which is vertically disposed, which comprisesthird and fourth reflective surfaces 128, 126 respectively, and whichlooks through the fourth reflective surface 126.

The optical re-orientation means 106 still further comprises a thirdperiscope arrangement 130 which is horizontally disposed, and whichcomprises fifth and sixth reflective surfaces 132, 134 respectively. Thethird periscope arrangement 130 looks through the fifth reflectivesurface 132 into the bottom of the second periscope arrangement 124 suchthat the camera looks into the reflective surface 128 and out of thereflective surface 126, after the reflective surfaces 134 and 132respectively. The third periscope arrangement 130 is such that the sixthreflective surface 134 is positioned underneath (but staggered withrespect to) the second reflective surface 122 so that the optical axisof the exit of the third periscope arrangement 130 is directlyunderneath the optical axis of the exit of the first periscopearrangement 108.

During use of the apparatus 202, the housing 204 will be placed over thefirst, second and third periscope arrangements 108, 124, 130respectively. During use of the apparatus 202, the opticalre-orientation means 106 is able to re-orient a pair of landscapestereoscopic images between a first orientation required for humanviewing and a second orientation required for recording with a singlecamera, or for later or simultaneous viewing from a single screen.

The various reflective surfaces 120, 122, 126, 128, 132 and 134 shown inthe first, second and third periscope arrangements 108, 124, 130 in FIG.5 are in the form of plain mirrors. These plain mirrors form twoseparate optical paths which culminate with a common positive lens 136.Each of the two optical paths begins with a negative lens 138, 140. Asused herein, references to a positive lens mean a convex lens, andreferences to a negative lens mean a concave lens. The convex andconcave lenses may take various forms including, for example, doubleconvex or planoconvex, and double concave or planoconcave.

In the apparatus 106 shown in FIG. 5, the path length through the mirrorsystem between the positive lens 136 and each negative lens 138, 140 isthe same. The positive lens 136 shares a focal plain with each negativelens 138, 140, such that light emerges parallel from the positive lens136, compatible with a camera focused for “infinity” distance.

The mirror 120 may be rotated about a vertical axis C for the purpose ofsetting convergence between the two images (horizontal alignment).

The mirror 126 may be rotated about its upper edge for the initialset-up of vertical image content alignment.

The mirror 128 may be rotated about its lower edge to minimise or adjustthe separation between the two images as recorded by the camera.

The mirror 132 and/or the mirror 134 may be rotated about their top orbottom edges to ensure that a vertical feature in one of thestereoscopic images is parallel with the same feature in the secondimage.

During use of the apparatus 106, only the mirror 120 needs to beadjustable in rotation by the camera user. The other settings may beachieved during initial set-up assembly.

For clarity of illustration in FIG. 5, the mirror location of eachmirror is shown inside one of six identical blocks. Each block has asquare base and a height similar to that of the two negative lenses 138,140.

The apparatus 106 shown in FIG. 5 is advantageous in that the separationof the stereoscopic lenses may be changed in order to enhance thestereoscopic differences of the two images. More specifically, themirror 120 may be moved in a first direction to the right. The mirror126 is moved away from the mirror 122 by the same amount that the mirror120 is moved away from the mirror 122. The mirrors 126, 128 and 132 donot move relative to each other. The mirrors 122 and 134 also do notmove relative to each other. The mirrors 122 and 134 are fixed inrelation to the camera. When the mirror 126 is moved, the two associatedmirrors 128 and 132 move at the same time and with the mirror 126. Atmaximum separation of mirrors 126, 120 it is preferable for the negativelenses 138, 140 to share the same focal plain as the positive lens 136by the camera, and the camera focus needs to be set for infinity. As themirrors 126, 120 are brought together with the associated lenses 138,140 respectively which move with the mirrors 126, 120 the two pathlengths get shorter. Focus needs then to be compensated by adjusting thecamera lens for a finite subject distance, such that the total combinedpower of the positive lens 136 and the camera's own lens is shortened bythe same amount as the reduction in path length to the two negativelenses 138, 140.

In a modification of the apparatus shown in FIG. 5, a positive lens withstraight edges, or lenses of other shapes, may be used.

Referring now to FIGS. 6-9 there are shown from different angles anexploded view of apparatus 302 for the optical manipulation of a pair oflandscape stereoscopic images.

The apparatus 302 may be regarded as a simplified version of theapparatus 202 shown in FIG. 5. For ease of understanding, similar partsin FIGS. 5 and 6-9 have been given the same reference numerals.

The apparatus 302 comprises two blocks 142, 144 into which the upperlevel of optical components and the lower ones are held together as twosub-assemblies. The positive convex lens 136 is held in a recess 146between two complete rims formed by bringing the two blocks 142, 144together. There is still provision for rotating reflective surface 120about a vertical axis. The lenses 138, 140 are negative lenses.

It is to be appreciated that the embodiment of the invention describedabove with reference to the accompanying drawings has been given by wayof example only and that modifications may be effected. Thus for exampleeither the three assembly structure of FIG. 5 or the simplified twoassembly structure of FIGS. 6-9 may operate inverted. A system based ona mirror image construction would also function, but in this case, thewrong image of the pair would be stacked on top at the location of thepositive lens 136, causing incompatibilities. The apparatus of theinvention may be used to capture live images. These may be monitored inreal time stereoscopically with a compatible viewer such as shown inFIG. 4 described above.

1. Apparatus for the optical manipulation of a pair of landscapestereoscopic images, which apparatus comprises a housing, and opticalre-orientation means positioned in the housing and for re-orientatingthe pair of landscape stereoscopic images between a first orientationselected from one of the orientations from the group consisting of topand bottom orientation and side-by-side orientation required for humanviewing and a second orientation being the other orientation of thegroup required for recording with a single external camera positionedadjacent to the apparatus and viewed from a single screen, the singlescreen being such that it has a first pair of sides which are shorterthan a second pair of sides, the second orientation being such thatthere is no top to bottom inversion of one of the landscape stereoscopicimages with respect to the other of the landscape stereoscopic images,the second orientation being such that the landscape stereoscopic imagesare rotated for display in each of two halves of the single screen suchthat longest sides of the landscape stereoscopic images are parallelwith the first pair of sides of the screen thereby maintaining a goodaspect ratio without the need for compression or stretching of the pairof landscape stereoscopic images, and the optical re-orientation meansbeing such that the pair of landscape stereoscopic images leave theoptical re-orientation means in a direction which is parallel to adirection in which the pair of landscape stereoscopic images enter theoptical re-orientation means, and the apparatus being characterised inthat the optical re-orientation means comprises: (i) a first periscopearrangement which is horizontally disposed, and which comprises firstand second reflective surfaces; (ii) a second periscope arrangementwhich is vertically disposed, which comprises third and fourthreflective surfaces, with the third reflective surface being the lowerreflective surface for reflecting out image light towards the singlecamera; and (iii) a third periscope arrangement which is horizontallydisposed, which comprises fifth and sixth reflective surfaces, whereinthe fifth reflective surface is facing and aligned with the thirdreflective surface of the second periscope arrangement, and which issuch that the sixth reflective surface is positioned underneath thesecond reflective surface so that the optical axis of the exit of thethird periscope arrangement is directly underneath the optical axis ofthe exit of the first periscope arrangement.
 2. Apparatus according toclaim 1 in which the reflective surfaces are prism reflective surfaces.3. Apparatus according to claim 1 in which the reflective surfaces aremirror reflective surfaces.
 4. Apparatus according to claim 1 in whichthe separation of two lenses, analogous to eye separation distance, isable to be varied below a maximum.
 5. Apparatus according to claim 1 inwhich the left edges and the right edges of the stereoscopic pair ofimages are able to be aligned by rotation of the first reflectivesurface about a vertical axis.
 6. Apparatus according to claim 1 inwhich at least some of the reflective surfaces are located in blocks.